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Zee, A.

Publications and source records attributed to Zee, A..

Electric dipole moment of the electron and of the neutron

It is shown that if Higgs-boson exchange mediates CP violation a significant electric dipole moment for the electron can result. Analogous effects can contribute to the neutron's electric dipole moment at a level competitive with Weinberg's three-gluon operator.

Barr, S. M.↗

Effective theory of the T- and P-breaking superconducting state

An effective theory of superconductivity based on a microscopic theory of the T- and P-breaking spin-liquid state is proposed. There are two independent gauge invariances broken by two separate condensates. The theory may be useful for phenomenological calculations. In particular, it is found that the H(c1) are different for magnetic fields with opposite orientations. It is also found that the polarization of an electromagnetic wave is rotated after reflection from these T- and P-breaking superconductors.

Wen, X. G.↗

Quantum disorder, duality, and fractional statistics in 2 + 1 dimensions

A low-energy equivalence between two apparently unrelated Lagrangians with fractional statistics is reported. Exploiting this equivalence, it is possible to study the quantum disordered phase of the nonlinear sigma model with Hopf term. It is found that the quasi-particles in the disordered phase also have fractional statistics. There appears to be a dual relationship between the ordered and disordered phases.

Wen, X. G.↗

Statistical mechanics and invariant perception

The problem of discrimination among ensembles of images generated by distortions of a prototype and the addition of noise is considered. As the noise level is increased, the discrimination task becomes qualitatively more difficult in that optimal discrimination requires the computation of increasingly longer-ranged correlations, or the solution of increasingly difficult optimization problems. These results suggest the use of such image ensembles in probing the computational abilities of the human visual system, and possible theoretical implications of such experiments are discussed.

Bialek, William↗

Possible form of vacuum deformation by heavy particles

The possibility is discussed that the lowest-energy state for certain quantum numbers involves a Higgs field polarized into a skyrmion-type configuration. In some models a new type of vacuum instability arises. Phenomenological consequences are indicated schematically.

Mackenzie, R.↗

Appearance of gauge structure in simple dynamical systems

By generalizing a construction of Berry and Simon, it is shown that non-Abelian gauge fields arise in the adiabatic development of simple quantum mechanical systems. Characteristics of the gauge fields are related to energy splittings, which may be observable in real systems. Similar phenomena are found for suitable classical systems.

Wilczek, F.↗

Linking numbers, spin, and statistics of solitons

The spin and statistics of solitons in the (2 + 1)- and (3 + 1)-dimensional nonlinear sigma models is considered. For the (2 + 1)-dimensional case, there is the possibility of fractional spin and exotic statistics; for 3 + 1 dimensions, the usual spin-statistics relation is demonstrated. The linking-number interpretation of the Hopf invariant and the use of suspension considerably simplify the analysis.

Wilczek, F.↗